Unit 4 Assignment Concepts of Biology by Amber Hawn

amberhawn351 — 2025-02-03 01:19:31 UTC

Mitosis is the process of cell division that results in 2 genetically identical daughter cells.

Interphase (Preparation Phase)

amberhawn351 — 2025-02-03 01:25:05 UTC

Interphase is when the cell grows & duplicates it's DNA in preparation for division.

Prophase

amberhawn351 — 2025-02-03 01:28:19 UTC

Prophase is when chromatin condenses into visible chromosomes.

The nuclear envelope begins to break down.

The mitotic spindle starts forming.

Metaphase

amberhawn351 — 2025-02-03 01:32:10 UTC

Metaphase is when chromosomes align at the cells equatorial plane (Metaphase Plate).

The spindle fibers attach to the centromeres of the chromosomes.

Anaphase

amberhawn351 — 2025-02-03 01:34:30 UTC

Anaphase is when the sister chromatics pull apart towards opposite poles of the cell by the spindle fibers.

Telophase

amberhawn351 — 2025-02-03 01:37:11 UTC

Telophase is when the chromatics reach the poles & begin to de-condense into chromatin.

The nuclear envelope reforms around each set of chromosomes.

Cytokinesis (not part of Mitosis but follows it)

amberhawn351 — 2025-02-03 01:40:13 UTC

Cytokinesis is when the cytoplasm divides,forming two daughter cells, each with identical genetic material.

Meiosis

amberhawn351 — 2025-02-03 01:45:51 UTC

Meiosis is the process of cell division that produces 4 genetically unique haploid gametes (sperm or egg cells).

Meiosis ensures genetic variation through crossing over (Prophase 1) & independent assortment (Metaphase 1) making each gamete unique.

It consists or 2 consecutive divisions Meiosis 1( reductional division & Meiosis 2- equational division.

Prophase 1 & 2

amberhawn351 — 2025-02-03 01:54:05 UTC

Prophase 1 is when chromosomes condense & become visible.

Homologous chromosomes pair up in a process called synapsis, forming tetrads.

Crossing over occurs, where homologous chromosomes exchange genetic material, increasing genetic diversity.

The nuclear envelope breaks down & spindle fibers form.

Prophase 2

Prophase 2 is when chromosomes condense again and the spindle apparatus reforms.

Metaphase 1&2

amberhawn351 — 2025-02-03 01:59:18 UTC

Metaphase 1 is when homologous chromosomes pair & aligns at the metaphase plate.

Spindle fibers attach to centromeres.

Metaphase 2

Metaphase 2 is when chromosomes align individually at the metaphase plate.

Anaphase 1&2

amberhawn351 — 2025-02-03 02:03:24 UTC

Anaphase 1 is when homologous chromosomes are pulled apart to opposite poles.(Sister chromatics remain together).

This reduces the chromosomes number by half.

Anaphase 2

Anaphase 2 is when sister chromatids are separated & pulled to opposite poles.

Telophase 1&2 & Cytokinesis

amberhawn351 — 2025-02-03 02:09:10 UTC

Telophase 1 & Cytokinesis is when chromosomes reach the poles & the nuclear membrane may reform.

The cytoplasm divides, producing 2 haploid cells, each with half the original chromosome number.

Telophase 2 & Cytokinesis

Telophase 2 is when chromosomes reach the poles, nuclear membranes reform, & the cytoplasm divides.

4 genetically unique haploid gametes are produced.

Number of divisions

amberhawn351 — 2025-02-03 02:12:57 UTC

Mitosis- one cell division. Produces 2 identical daughter cells.

Meiosis- 2 consecutive cell division. Produces 4 genetically unique daughter cells.

Genetic Identity

amberhawn351 — 2025-02-03 02:14:45 UTC

Mitosis- daughter cells are clones of the parent cell, maintaining genetic consistency.

Meiosis- daughter cells are genetically different due to crossing over & independent assortment.

Chromosome Numbers

amberhawn351 — 2025-02-03 02:16:17 UTC

Mitosis- maintains the diploid chromosome number.

Meiosis- reduces the haploid for gamete formation.

Pairing of Homogous Chromosomes

amberhawn351 — 2025-02-03 02:18:24 UTC

Mitosis- homologous chromosomes do not pair or exchange genetic material.

Meiosis- homologous chromosomes pair up & undergo crossing over, leading to genetic diversity.

Separation of Chromosomes

amberhawn351 — 2025-02-03 02:20:26 UTC

Mitosis- sister chromatids separate in anaphase.

Meiosis 1- Homogous Chromosomes separate, reducing chromosomes number.

Meiosis 2- sister chromatids separate.

Purpose

amberhawn351 — 2025-02-03 02:22:21 UTC

Mitosis- growth, repair & a sexual reproduction. Producing identical cells.

Meiosis- sexual reproduction producing genetically diverse gametes.

Crossing over (Prophase 1)

amberhawn351 — 2025-02-03 02:28:19 UTC

Homologous chromosomes pair up and exchange segments of genetic material at points called Chiasmata.

The process recombines genes from material & paternal Chromosomes, creating new allele combinations.

As a result the chromosomes that separate into gametes are not identical to those inherited from the parents.

Independent Assortment (Metaphase 1)

amberhawn351 — 2025-02-03 02:32:15 UTC

Homologous chromosome pairs align randomly at the metaphase plate.

Each pair sorts independently of the others leading to different combinations of maternal & paternal chromosomes in gametes.

The process ensures that each gamete & ultimately each off spring is genetically unique, promoting diversity within a species.

Mendel's law of Independent Assortment

amberhawn351 — 2025-02-03 02:36:21 UTC

It states that alleles for different genes segregate independently of one another during gamete formation (Meiosis).

This means that the inheritance of one trait does not affect the inheritance of another, as long as the genes are located on different Chromosomes or far apart on the same chromosome.

Mendel's Law helps explain genetic variation & is fundamental to understanding how traits are inherited across generations.

amberhawn351 — 2025-02-03 02:40:41 UTC

Fowler,S.,Roush,R.& Wise, J. (2023,Jan 9) Concepts of Biology Open Stax College